Sinn Féin leader Mary Lou McDonald has denied her party covered up the sexual abuse of Máiría Cahill by an alleged provisional IRA member, despite serious concerns over an internal inquiry conducted into what happened.

Ms McDonald was forced to reject the claim after a Police Ombudsman for Northern Ireland report last week found the police force failed Ms Cahill and that the then RUC was aware of a provisional IRA inquiry but did not investigate it.

In the immediate aftermath of the report last week, Ms McDonald apologised in a statement to Ms Cahill without making any reference to the internal inquiry, a situation heavily criticised by Ms Cahill.

Asked today if she accepts the case was covered up by either Sinn Féin or the provisional IRA, Ms McDonald said "the complainants in this awful case have been through an absolute ordeal", but denied her party did anything wrong,

However, despite apologising again to Ms Cahill, the Sinn Féin leader controversially added she is "not a spook, not a spy" and has no access to potentially archived files.

"There is no allegation of a cover-up by Sinn Féin. As regards your other question around intelligence reports, of course, I'm not in a position to answer that, I'm not a spook, I'm not a spy, I'm not a police officer, I'm the leader of a political party.

"And I have a responsibility, of course, to ensure our processes and procedures are how they are meant to be. I'm not going to answer for police failures, which is what the report is about.

"Yes I stand over that, there has been no cover-up. And I would just like you to reflect on the fact that an allegation of a cover-up is a serious and criminal allegation."

"It's not true, it's not the case, and there is no evidence of it. Because it simply didn't happen," Ms McDonald said.

She added that while Ms McDonald has side-stepped questions on whether her alleged provisional IRA abuser, Martin Morris, was a member of Sinn Féin, the ombudsman's report has quoted newspaper records from the time showing he was a Sinn Féin member.